ANO1/TMEM16A regulates process maturation in radial glial cells in the developing brain.

Neural stem cells (NSCs) are primary progenitor cells in the early developmental stage in the brain that initiate a diverse lineage of differentiated neurons and glia. Radial glial cells (RGCs), a type of neural stem cell in the ventricular zone, are essential for nurturing and delivering new immature neurons to the appropriate cortical target layers. Here we report that Anoctamin 1 (ANO1)/TMEM16A, a Ca2+-activated chloride channel, mediates the Ca2+-dependent process extension of RGCs. ANO1 is highly expressed and functionally active in RGCs of the mouse embryonic ventricular zone. Knockdown of ANO1 suppresses RGC process extension and protrusions, whereas ANO1 overexpression stimulates process extension. Among various trophic factors, brain-derived neurotrophic factor (BDNF) activates ANO1, which is required for BDNF-induced process extension in RGCs. More importantly, Ano1-deficient mice exhibited disrupted cortical layers and reduced cortical thickness. We thus conclude that the regulation of RGC process extension by ANO1 contributes to the normal formation of mouse embryonic brain.

A simple method for extracting phycocyanin from Arthrospira (Spirulina) platensis by autolysis.

Phycocyanin (PC) is a natural blue pigment that has great commercial value in food and pharmaceutical industry. Arthrospira (Spirulina) platensis is a photosynthetic spiral-shaped cyanobacterium containing a rich PC pigment. Autolysis is the enzymatic digestion of cells by the action of its own enzymes. To develop an effective and economical extraction process, an autolysis process was incorporated into the conventional freezing-thawing method. In the present study, 91% of maximal extraction yield of PC with 1.194 purity (A620/A280) was obtained via autolysis after 3 h of incubation at 37 °C without using an extraction salt solution or a successive freezing-thawing process. In addition to temperature, the initial concentration of bicarbonate in growth medium and the concentration of wet biomass are important parameters that influence the extraction yield of PC by autolysis.

Tuna byproducts as a fish-meal in tilapia aquaculture.

Potentiality of the use of tuna byproducts as a fish-meal replacement on Nile tilapia (Oreochromis niloticus) was examined for 84 weeks by tracking the concentrations of cadmium and mercury in the internal organs, muscles and fish whole body through generation including their immature eggs and their larvae. The results confirmed that the tuna byproducts can be used as a fish-meal substitute in tilapia aquaculture, because their acceptable ranges for cadmium and mercury consequently did not exceed the food safety values (both < 0.5 mg kg-1), despite their proportional increases in the fish body. The use of tuna byproducts as a protein source is expected to reduce the cost of feed with other fishmeal substitutes in tilapia aquaculture. However, fish (flounder) indiscriminately consuming tuna byproduct feed were prohibited and recalls of sales were issued by the government (July 2018, Republic of Korea), as the threshold for mercury in the fish bodies had been exceeded (0.6-0.8 mg kg-1). Further study of the use of tuna byproducts as fishmeal replacements for other species in aquaculture is needed, as concentration ratios can vary depending on the species.

Anoctamin 1 (TMEM16A) is essential for testosterone-induced prostate hyperplasia.

Benign prostatic hyperplasia (BPH) is characterized by an enlargement of the prostate, causing lower urinary tract symptoms in elderly men worldwide. However, the molecular mechanism underlying the pathogenesis of BPH is unclear. Anoctamin1 (ANO1) encodes a Ca(2+)-activated chloride channel (CaCC) that mediates various physiological functions. Here, we demonstrate that it is essential for testosterone-induced BPH. ANO1 was highly amplified in dihydrotestosterone (DHT)-treated prostate epithelial cells, whereas the selective knockdown of ANO1 inhibited DHT-induced cell proliferation. Three androgen-response elements were found in the ANO1 promoter region, which is relevant for the DHT-dependent induction of ANO1. Administration of the ANO1 blocker or Ano1 small interfering RNA, inhibited prostate enlargement and reduced histological abnormalities in vivo. We therefore concluded that ANO1 is essential for the development of prostate hyperplasia and is a potential target for the treatment of BPH.

Cellular functions of TMEM16/anoctamin.

Ca(2+)-activated Cl(-) channels (CaCCs) are a class of Cl(-) channels activated by intracellular Ca(2+) that are known to mediate numerous physiological functions. In 2008, the molecular identity of CaCCs was found to be anoctamin 1 (ANO1/TMEM16A). Its roles have been studied in electrophysiological, histological, and genetic aspects. ANO1 is known to mediate Cl(-) secretion in secretory epithelia such as airways, salivary glands, intestines, renal tubules, and sweat glands. ANO1 is a heat sensor activated by noxious heat in somatosensory neurons and mediates acute pain sensation as well as chronic pain. ANO1 is also observed in vascular as well as airway smooth muscles, controlling vascular tone as well as airway hypersensitivity. ANO1 is upregulated in numerous types of cancers and thus thought to be involved in tumorigenesis. ANO1 is also found in proliferating cells. In addition to ANO1, involvement of its paralogs in pathophysiological conditions was also reported. ANO2 is involved in olfaction, whereas ANO6 works as a scramblase whose mutation causes a rare bleeding disorder, the Scott syndrome. ANO5 is associated with muscle and bone diseases. Recently, an X-ray crystal structure of a fungal TMEM16 was reported, which explains a precise molecular gating mechanism as well as ion conduction or phospholipid transport across the plasma membrane.

Trusting Social Media as a Source of Health Information: Online Surveys Comparing the United States, Korea, and Hong Kong.

BACKGROUND: The Internet has increasingly become a popular source of health information by connecting individuals with health content, experts, and support. More and more, individuals turn to social media and Internet sites to share health information and experiences. Although online health information seeking occurs worldwide, limited empirical studies exist examining cross-cultural differences in perceptions about user-generated, experience-based information compared to expertise-based information sources. OBJECTIVE: To investigate if cultural variations exist in patterns of online health information seeking, specifically in perceptions of online health information sources. It was hypothesized that Koreans and Hongkongers, compared to Americans, would be more likely to trust and use experience-based knowledge shared in social Internet sites, such as social media and online support groups. Conversely, Americans, compared to Koreans and Hongkongers, would value expertise-based knowledge prepared and approved by doctors or professional health providers more. METHODS: Survey questionnaires were developed in English first and then translated into Korean and Chinese. The back-translation method ensured the standardization of questions. Surveys were administered using a standardized recruitment strategy and data collection methods. RESULTS: A total of 826 participants living in metropolitan areas from the United States (n=301), Korea (n=179), and Hong Kong (n=337) participated in the study. We found significant cultural differences in information processing preferences for online health information. A planned contrast test revealed that Koreans and Hongkongers showed more trust in experience-based health information sources (blogs: t451.50=11.21, P<.001; online support group: t455.71=9.30, P<.001; social networking sites [SNS]: t466.75=11.36, P<.001) and also reported using blogs (t515.31=6.67, P<.001) and SNS (t529.22=4.51, P<.001) more frequently than Americans. Americans showed a stronger preference for using expertise-based information sources (eg, WebMD and CDC) compared to Koreans and Hongkongers (t360.02=3.01, P=.003). Trust in expertise-based information sources was universal, demonstrating no cultural differences (Brown-Forsythe F2,654=1.82, P=.16). Culture also contributed significantly to differences in searching information on behalf of family members (t480.38=5.99, P<.001) as well as to the goals of information searching. CONCLUSIONS: This research found significant cultural differences in information processing preferences for online health information. Further discussion is included regarding effective communication strategies in providing quality health information.

Two helices in the third intracellular loop determine anoctamin 1 (TMEM16A) activation by calcium.

Anoctamin 1 (ANO1)/TMEM16A is a Cl(-) channel activated by intracellular Ca(2+) mediating numerous physiological functions. However, little is known of the ANO1 activation mechanism by Ca(2+). Here, we demonstrate that two helices, "reference" and "Ca(2+) sensor" helices in the third intracellular loop face each other with opposite charges. The two helices interact directly in a Ca(2+)-dependent manner. Positively and negatively charged residues in the two helices are essential for Ca(2+)-dependent activation because neutralization of these charges change the Ca(2+) sensitivity. We now predict that the Ca(2+) sensor helix attaches to the reference helix in the resting state, and as intracellular Ca(2+) rises, Ca(2+) acts on the sensor helix, which repels it from the reference helix. This Ca(2+)-dependent push-pull conformational change would be a key electromechanical movement for gating the ANO1 channel. Because chemical activation of ANO1 is viewed as an alternative means of rescuing cystic fibrosis, understanding its gating mechanism would be useful in developing novel treatments for cystic fibrosis.

Utilization of seawater for cost-effective cultivation and harvesting of Scenedesmus obliquus.

Microalgae hold great promise as a source of biofuels and biochemicals. The main obstacles to their industrial application are the high cultivation and downstream costs related to media and harvesting. In the work, we explored the multiple potentials of seawater to address key issues relating to the cultivation of Scenedesmus obliquus. Seawater can sufficiently replace some of the key elements in BG11 medium such as MgSO4, CaCl2, and NaCO3, and its use can significantly reduce the quantity of water required for the preparation of culture media. Among our results, the total chlorophyll content in cells grown in modified BG11 using 10 % (v/v) seawater was increased 1.47-fold without sacrificing biomass or lipid production. More than 70 % of the total algal biomass was auto-flocculated within one hour when cells were grown in seawater-supplemented media, which compares very favorably with a yield of only 3 % from cells grown in BG11.

Optimization of variables affecting the direct transesterification of wet biomass from Nannochloropsis oceanica using ionic liquid as a co-solvent.

Ionic liquids have many applications, one of which entails their utilization as powerful solvents. In the present study, various experimental conditions of ionic liquid-mediated direct transesterification were investigated in terms of lipid-extracting ionic liquids, catalyst, reaction time, reaction temperature and volume of methanol to achieve effective FAME conversion with wet microalgal feedstock, Nannochloropsis oceanica. With ionic liquid, [Bmim][CF3SO3], highest fatty acid methyl ester (FAME) yield was shown. Among many experimental parameters, the two most critical factors to enhance FAME conversion were characteristic of ionic liquids and volume of methanol. Optimized ionic liquid-mediated direct transesterification of wet N. oceanica, compared with a control experiment using chloroform and methanol, increased the FAME conversion yield by 11-fold.

TRPM2 mediates the lysophosphatidic acid-induced neurite retraction in the developing brain.

Intracellular Ca(2+) signal is a key regulator of axonal growth during brain development. As transient receptor potential (TRP) channels are permeable to Ca(2+) and mediate numerous brain functions, it is conceivable that many TRP channels would regulate neuronal differentiation. We therefore screened TRP channels that are involved in the regulation of neurite growth. Among the TRP channels, the Trpm2 level was inversely associated with neurite growth. TRPM2 was highly expressed in embryonic brain. Pharmacological perturbation or knockdown of TRPM2 markedly increased the axonal growth, whereas its overexpression inhibited the axonal growth. Addition of ADP ribose, an endogenous activator of TRPM2, to PC12 cells significantly repressed the axonal growth. TRPM2 was actively involved in the neuronal retraction induced by cerebrospinal fluid-rich lysophosphatidic acid (LPA). More importantly, neurons isolated from the brain of Trpm2-deficient mice have significantly longer neurites with a greater number of spines than those obtained from the brain of wild-type mice. Therefore, we conclude that TRPM2 mediates the LPA-induced suppression of axonal growth, which provides a long-sought mechanism underlying the effect of LPA on neuronal development.

Anoctamin 1 contributes to inflammatory and nerve-injury induced hypersensitivity.

BACKGROUND: Various pathological conditions such as inflammation or injury can evoke pain hypersensitivity. That represents the response to innocuous stimuli or exaggerated response to noxious stimuli. The molecular mechanism based on the pain hypersensitivity is associated with changes in many of ion channels in dorsal-root ganglion (DRG) neurons. Anoctamin 1 (ANO1/TMEM16A), a Ca2+ activated chloride channel is highly visible in small DRG neurons and responds to heat. Mice with an abolished function of ANO1 in DRG neurons demonstrated attenuated pain-like behaviors when exposed to noxious heat, suggesting a role in acute thermal nociception. In this study, we further examined the function of ANO1 in mediating inflammation- or injury-induced hyperalgesia or allodynia. RESULTS: Using Advillin/Ano1fl/fl (Adv/Ano1fl/fl) mice that have a functional ablation of Ano1 mainly in DRG neurons, we were able to determine its role in mediating thermal hyperalgesia and mechanical allodynia induced by inflammation or nerve injury. The thermal hyperalgesia and mechanical allodynia induced by carrageenan injection and spared-nerve injury were significantly reduced in Adv/Ano1fl/fl mice. In addition, flinching or licking behavior after bradykinin or formalin injection was also significantly reduced in Adv/Ano1fl/fl mice. Since pathological conditions augment nociceptive behaviors, we expected ANO1's contribution to the excitability of DRG neurons. Indeed, the application of inflammatory mediators reduced the threshold for action potential (rheobase) or time for induction of the first action potential in DRG neurons isolated from control (Ano1fl/fl) mice. These parameters for neuronal excitability induced by inflammatory mediators were not changed in Adv/Ano1fl/fl mice, suggesting an active contribution of ANO1 in augmenting the neuronal excitability. CONCLUSIONS: In addition to ANO1's role in mediating acute thermal pain as a heat sensor, ANO1 is also capable of augmenting the excitability of DRG neurons under inflammatory or neuropathic conditions and thereby aggravates inflammation- or tissue injury-induced pathological pain.

Multi-level functionality of social media in the aftermath of the Great East Japan Earthquake.

This study examines the multi-level functionalities of social media in the aftermath of the Great East Japan Earthquake of 11 March 2011. Based on a conceptual model of multi-level story flows of social media (Jung and Moro, 2012), the study analyses the multiple functionalities that were ascribed to social media by individuals, organisations, and macro-level social systems (government and the mass media) after the earthquake. Based on survey data, a review of Twitter timelines and secondary sources, the authors derive five functionalities of social media: interpersonal communications with others (micro level); channels for local governments; organisations and local media (meso level); channels for mass media (macro level); information sharing and gathering (cross level); and direct channels between micro-/meso- and macro-level agents. The study sheds light on the future potential of social media in disaster situations and suggests how to design an effective communication network to prepare for emergency situations.

Use of extracts from oyster shell and soil for cultivation of Spirulina maxima.

Calcium ion and trace metals play important roles in various metabolisms of photosynthetic organisms. In this study, simple methods were developed to extract calcium ion and micronutrients from oyster shell and common soil, and the prepared extracts were tested as a replacement of the corresponding chemicals that are essential for growth of microalgae. The oyster shell and soil were treated with 0.1 M sodium hydroxide or with 10 % hydrogen peroxide, respectively. The potential application of these natural sources to cultivation was investigated with Spirulina maxima. When compared to standard Zarrouk medium, the Spirulina maxima cultivated in a modified Zarrouk media with elements from oyster shell and soil extract exhibited increases in biomass, chlorophyll, and phycocyanin by 17, 16, and 64 %, respectively. These results indicate that the extracts of oyster shell and soil provide sufficient amounts of calcium and trace metals for successful cultivation of Spirulina maxima.

Effects of molten-salt/ionic-liquid mixture on extraction of docosahexaenoic acid (DHA)-rich lipids from Aurantiochytrium sp. KRS101.

In this study, lipid extraction from Aurantiochytrium sp. was performed using a molten-salt/ionic-liquid mixture. The total fatty acid content of Aurantiochytrium sp. was 478.8 mg/g cell, from which 145 mg/g cell (30.3% of total fatty acids) of docosahexaenoic acid (DHA) was obtained. FeCl3·6H2O showed a high lipid extraction yield (207.9 mg/g cell), when compared with that of [Emim]OAc, which was only 118.1 mg/g cell; notably however, when FeCl3·6H2O was mixed with [Emim]OAc (5:1, w/w), the yield was increased to 478.6 mg/g cell. When lipid was extracted by the FeCl3·6H2O/[Emim]OAc mixture at a 5:1 (w/w) blending ratio under 90 °C, 30 min reaction conditions, the fatty acid content of the extracted lipid was a high purity 997.7 mg/g lipid, with most of the DHA having been extracted (30.2% of total fatty acids). Overall, lipid extraction from Aurantiochytrium sp. was enhanced by the synergistic effects of the molten-salt/ionic-liquid mixture with different ions.

Axonal neuropathy-associated TRPV4 regulates neurotrophic factor-derived axonal growth.

Spinal muscular atrophy and hereditary motor and sensory neuropathies are characterized by muscle weakness and atrophy caused by the degenerations of peripheral motor and sensory nerves. Recent advances in genetics have resulted in the identification of missense mutations in TRPV4 in patients with these hereditary neuropathies. Neurodegeneration caused by Ca(2+) overload due to the gain-of-function mutation of TRPV4 was suggested as the molecular mechanism for the neuropathies. Despite the importance of TRPV4 mutations in causing neuropathies, the precise role of TRPV4 in the sensory/motor neurons is unknown. Here, we report that TRPV4 mediates neurotrophic factor-derived neuritogenesis in developing peripheral neurons. TRPV4 was found to be highly expressed in sensory and spinal motor neurons in early development as well as in the adult, and the overexpression or chemical activation of TRPV4 was found to promote neuritogenesis in sensory neurons as well as PC12 cells, whereas its knockdown and pharmacologic inhibition had the opposite effect. More importantly, nerve growth factor or cAMP treatment up-regulated the expression of phospholipase A(2) and TRPV4. Neurotrophic factor-derived neuritogenesis appears to be regulated by the phospholipase A(2)-mediated TRPV4 pathway. These findings show that TRPV4 mediates neurotrophic factor-induced neuritogenesis in developing peripheral nerves. Because neurotrophic factors are essential for the maintenance of peripheral nerves, these findings suggest that aberrant TRPV4 activity may lead to some types of pathology of sensory and motor nerves.

Voluntary movements as a possible non-reflexive pain assay.

BACKGROUND: The quantification of pain intensity in vivo is essential for identifying the mechanisms of various types of pain or for evaluating the effects of different analgesics. A variety of behavioral tests for pain measurement have been devised, but many are limited because animals are physically restricted, which affects pain sensation. In this study, pain assessment was attempted with minimal physical restriction, and voluntary movements of unrestrained animals were used to evaluate the intensities of various types of pain. RESULTS: The number of times animals reared or total distances traveled was measured using a motion-tracking device and found to be markedly reduced in carrageenan-induced inflammatory, acetic acid-induced visceral, and streptozotocin-induced neuropathic pain tests. These two voluntary movement parameters were found to be highly correlated with paw withdrawal latency from irradiating heat. In addition, these parameters were markedly reversed by morphine and by non-steroidal anti-inflammatory drugs in inflammatory pain models. These parameters were also useful to detect hypoalgesia in TRPV1⁻/⁻ mice. CONCLUSIONS: These results suggest that parameters of voluntary movement, such as, number of rearing and total distance moved, are effective indicators of pain intensity for many types of pain and that they can be used to evaluate degree of pain perception.

Photometric determination of peracetic acid by reaction with potassium iodide solution.

Peracetic acid (PAA) is a strong oxidizing agent and is considered an ideal disinfectant because of its excellent disinfecting effect at low concentration, low corrosiveness, and relatively low cost. Commercially available PAA solution is a mixture of PAA, acetic acid, and hydrogen peroxide. However, PAA naturally decomposes faster than hydrogen peroxide. Therefore, accurately quantifying the concentration of PAA in the PAA peroxide mixture via a simple method is important. In the present study, a new method was developed, in which the spectral change of I- ion at 226 nm and the absorption value from the generated I2 at 460 nm were used to determine the concentration of PAA, following a chemical reaction with 0.1 mM potassium iodide (KI) solution without the use of any other chemicals. In this work, the measurable concentration of PAA was as low as 0.0001 wt% (13.1 µM) and as high as 0.0015 wt% (197.2 µM), which matches well with high linearity (99.95% at 226 nm and 99.91% at 460 nm). This work could also be the high selectivity method toward PAA in the PAA peroxide mixture.

A simple spectrophotometric determination of hydrogen peroxide solution via spectral delta from redox reaction with sodium hypochlorite.

Hydrogen peroxide (H2O2) is widely used in the synthesis of organic chemicals, bleaching of paper pulp, and the treatment of wastewater and as a food additive, important mediator of redox processes in natural water, and a disinfectant. However, H2O2 stock solution is unstable and slowly decomposes when exposed to, for example, light, elevated temperatures, or metal compounds. Therefore, the ability to measure the exact concentration of H2O2 stock solution is important for its proper use in diverse applications. This work proposes a simple method for the spectrophotometric determination of H2O2 solution via chemical reaction with sodium hypochlorite that is inexpensive and easy to acquire. The proposed method is based on the stoichiometric spectral change of hypochlorite ion at 292.5 nm following a redox reaction with a sample solution of H2O2. Due to high relationship between the spectral delta value and the applied H2O2 concentration (0.00188-0.03000%), H2O2 stock solution can be easily quantified.

Disruption of bis leads to the deterioration of the vascular niche for hematopoietic stem cells.

The stem cell niche plays an important role in the microenvironmental regulation of hematopoietic stem cells, but the integration of niche activity remains poorly understood. In this study, we show that a functional deficiency of Bis/BAG-3/CAIR-1, a protein related to apoptosis and the response to cellular stress, results in perturbation of the vascular stem cell niche, causing a series of hematopoietic derangements. Mice with a targeted disruption of bis (bis(-/-)) exhibited a loss of hematopoietic stem cells and defective B-cell development. However, this hematological defect of bis(-/-) mice was not reproduced when bis(-/-) bone marrow cells were transplanted into bis(+/+) recipients. Moreover, bis(+/+) bone marrow cells, when transplanted into bis(-/-) mice, reproduced the same defect as bis(-/-) cells, pointing to the microenvironmental origin of the phenotypes. Subsequent analysis of bis(-/-) mice bone marrow revealed a characteristic defect in the vascular stem cell niche that included the defective growth of stromal progenitor cells in colony forming unit-fibroblasts, the defect in sinusoidal endothelium, and the loss of stromal cells expressing CXCL-12 or IL-7 in the bone marrow. In contrast, no abnormalities were observed in the growth and hematopoietic supporting activities of osteoblasts from bis(-/-) mice bone marrows. Collectively, these results indicate that Bis functions to mediate cellular regulation of the stem cell niche on the vascular compartment and suggest that the vascular and osteoblastic compartments of the stem cell niche can be independently regulated during the in vivo orchestration of hematopoiesis.

Potential of Bacterial Strains Isolated from Coastal Water for Wastewater Treatment and as Aqua-Feed Additives.

Bacteria have various and sustained effects on humans in various fields: molecular biology, biomedical science, environmental/food industry, etc. This study was conducted to evaluate the wastewater treatment capacity and feed-additive fish-growth effect of four strains of bacteria: Pseudoalteromonas mariniglutinosa, Psychrobacter celer, Bacillus albus, and Bacillus safensis. In a wastewater degradation experiment, (i) nitrate-N and nitrite-N were removed within 1 h in all of the 4 bacterial strains; (ii) the removal rates of TAN and TN were higher in all of the strains relative to the B. subtilis. In a feed-additive experiment (5% Kg-1), (i) the growth of fish was higher in all of the 4 bacterial strains with the B. subtilis relative to the commercial feed; (ii) there was no significant growth difference for B. albus and B. safensis relative to the B. subtilis, but growth was higher in P. mariniglutinosa and P. celer. The results indicated that the 4 bacterial strains can be effectively utilized for biological wastewater treatment processes and as aqua-feed.